I know what the books say, but I don't have a common ground and haven't
had for years. To start with, I'd unhook the grounds. ground loops can
do very strange things...
73
Butch
WA0VJR
Node 3148
Wallace, ks.
On Sat, 20 Feb 2016, Tom Behler wrote:
> Bob:
>
> But wouldn't you want some sort of a common RF ground somewhere? This is
> why I use the common ground point on my MFJ window feed-through panel, and
> feed it to the ground rod below my shack window. I had thought of
> disconnecting the long ground wire myself, but didn't know what to replace
> it with. Perhaps a common ground connection to the screw on one of the
> electrical outlets in the shack would help, but I would think everything
> would be covered that way via the ground pin on the power cords for my
> various pieces of equipment.
>
> Tom Behler: KB8TYJ
>
>
> -----Original Message-----
> From: For blind ham radio operators [mailto:[log in to unmask]]
> On Behalf Of Bob Tinney
> Sent: Saturday, February 20, 2016 9:38 AM
> To: [log in to unmask]
> Subject: Re: RFI question
>
> Tom,
>
> Either your long ground wire is causing a radiating ground loop or you've
> got RF coming back down the shield of your coax. You could try a coax choke
> at the antenna or try changing the length of your ground wire or try tuning
> it, or try just disconnecting it
>
> Bob, K8LR, [log in to unmask]
>
> On 2/19/2016 11:43 PM, Tom Behler wrote:
>> This is a multipart message in MIME format.
>>
>> ------=_NextPart_000_0010_01D16B6F.5C4D5990
>> Content-Type: text/plain;
>> charset="us-ascii"
>> Content-Transfer-Encoding: 7bit
>>
>> Hello, everyone.
>>
>>
>>
>> I know I'm going to get a lot of different opinions on this question,
>> but here goes:
>>
>>
>>
>> I have been noticing lately that my RFI problems seem to be getting
>> worse here at the home QTH.
>>
>>
>>
>> In particular, they seem worse when I'm on CW, and appear on different
>> bands to different degrees. The fact that the problems seem worse on
>> CW does not surprise me, due to the nature of that mode in comparison
>> to SSB, for example.
>>
>>
>>
>> What does baffle me is that the problems seem to be getting worse in
>> general.
>>
>>
>>
>> For example, when I was playing around a bit in the ARRL International
>> DX CW contest for an hour or so tonight, I tried going back to a few
>> stations with approx. 500 watts, using my MFJ998 and ALS600 with the
>> TS590, and I set off the carbon monoxide detector downstairs on the
>> main floor of our house. On another occasion earlier in the month, I
>> was running 100 watts on CW on 160 meters, and I tripped one of the
>> circuit breakers in our house, and caused my wife problems when she was
> using her laptop computer in another room.
>>
>>
>>
>> I have checked the common ground point on my MFJ feed-through panel,
>> and the ground cables for my TS590, MFJ998, and ALS600. All seem to
>> be solid, at least here in the shack. The common ground point on the
>> MFJ feed-through panel has a cable outside my second-floor shack
>> window that runs down to a copper ground rod that is connected to the
>> ground on the power box to the house.
>>
>>
>>
>> I have not checked the outside ground connections at the ground rod,
>> and may try to do that tomorrow.
>>
>>
>>
>> My initial thinking is that RF is either coming through the house
>> electrical lines, through our cable modem and router, or both.
>>
>>
>>
>> I am planning on investing in some RF chokes as Steve (KW3A) has
>> suggested, and possibly one or two Buxcom Line Isolators like Butch
>> uses, but am wondering if I'm missing something obvious that I should
> check into first.
>>
>>
>>
>> Any thoughts would be appreciated.
>>
>>
>>
>> Tom Behler: KB8TYJ
>>
>>
>>
>>
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>> link=3Dblue = vlink=3Dpurple><div class=3DWordSection1><p
>> class=3DMsoNormal>Hello, = everyone.<o:p></o:p></p><p
>> class=3DMsoNormal><o:p> </o:p></p><p = class=3DMsoNormal>I know
>> I’m going to get a lot of different = opinions on this question,
>> but here goes:<o:p></o:p></p><p =
>> class=3DMsoNormal><o:p> </o:p></p><p class=3DMsoNormal>I have
>> been = noticing lately that my RFI problems seem to be getting worse
>> here at = the home QTH.<o:p></o:p></p><p
>> class=3DMsoNormal><o:p> </o:p></p><p = class=3DMsoNormal>In
>> particular, they seem worse when I’m on CW, = and appear on
>> different bands to different degrees. The fact that = the
>> problems seem worse on CW does not surprise me, due to the nature of =
>> that mode in comparison to SSB, for example.<o:p></o:p></p><p =
>> class=3DMsoNormal><o:p> </o:p></p><p class=3DMsoNormal>What does
>> = baffle me is that the problems seem to be getting worse in =
>> general.<o:p></o:p></p><p class=3DMsoNormal><o:p> </o:p></p><p =
>> class=3DMsoNormal>For example, when I was playing around a bit in the
>> = ARRL International DX CW contest for an hour or so tonight, I tried
>> = going back to a few stations with approx. 500 watts, using my MFJ998
>> and =
>> ALS600 with the TS590, and I set off the carbon monoxide detector =
>> downstairs on the main floor of our house. On another occasion =
>> earlier in the month, I was running 100 watts on CW on 160 meters, and
>> I = tripped one of the circuit breakers in our house, and caused my
>> wife = problems when she was using her laptop computer in another =
>> room.<o:p></o:p></p><p class=3DMsoNormal><o:p> </o:p></p><p =
>> class=3DMsoNormal>I have checked the common ground point on my MFJ =
>> feed-through panel, and the ground cables for my TS590, MFJ998, and =
>> ALS600. All seem to be solid, at least here in the shack.
>> = The common ground point on the MFJ feed-through panel has a cable =
>> outside my second-floor shack window that runs down to a copper ground
>> = rod that is connected to the ground on the power box to the =
>> house.<o:p></o:p></p><p class=3DMsoNormal><o:p> </o:p></p><p =
>> class=3DMsoNormal>I have not checked the outside ground connections at
>> = the ground rod, and may try to do that tomorrow.<o:p></o:p></p><p =
>> class=3DMsoNormal><o:p> </o:p></p><p class=3DMsoNormal>My initial
>> = thinking is that RF is either coming through the house electrical
>> lines, = through our cable modem and router, or both.<o:p></o:p></p><p
>> = class=3DMsoNormal><o:p> </o:p></p><p class=3DMsoNormal>I am =
>> planning on investing in some RF chokes as Steve (KW3A) has suggested,
>> = and possibly one or two Buxcom Line Isolators like Butch uses, but
>> am = wondering if I’m missing something obvious that I should
>> check = into first.<o:p></o:p></p><p
>> class=3DMsoNormal><o:p> </o:p></p><p = class=3DMsoNormal>Any
>> thoughts would be appreciated.<o:p></o:p></p><p =
>> class=3DMsoNormal><o:p> </o:p></p><p class=3DMsoNormal>Tom
>> Behler: = KB8TYJ<o:p></o:p></p><p =
>> class=3DMsoNormal><o:p> </o:p></p></div></body></html>
>> ------=_NextPart_000_0010_01D16B6F.5C4D5990--
>
>
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